1. Field of the Invention
The present invention relates to a media feeding system. More specifically, a media feeding system with a rotating pick arm and a rotating media restrainer is disclosed.
2. Description of the Prior Art
Media feeding systems are used to deliver media to a device, such as a fax machine, scanner, copier, printer, etc. The media is usually sheets of paper, but can also include plastic for transparencies, film, envelopes, etc. The media is typically stacked, and the media feeding system pulls the top sheet from the stack and delivers it to the device. Media feeding systems typically involve a so-called pick roller, which is a wheel that uses friction to push the top sheet or sheets from the stacked media, and a media separator. The media separator ensures that only a single sheet at a time is delivered on to the device, i.e., that only a single sheet of paper is fed into a printer.
Please refer to FIG. 1. FIG. 1 is a perspective view of a prior art media feeding system 10 for a printer, as disclosed in U.S. Pat. No. 5,971,390. Briefly, the media feeding system 10 comprises a media tray 12, a pick assembly 14 and a media separator 16. The pick assembly 14 comprises a pick roller 18, which pushes a sheet from the media tray 12 towards the media separator 16. The media separator 16 is a pad with a high coefficient of friction. When two sheets are pushed by the pick roller 18 past the media separator 16, the bottom sheet is stopped by the friction pad, and the top sheet slides over the bottom sheet to continue on towards the printer. In this manner, only a single sheet of media, such as paper, is fed into the printer.
The pick assembly 14 also comprises a spring (not shown), or some other such element, to provide a torque that pushes the pick roller 18 down onto the stacked media. This ensures that a sufficient amount of frictional force is available between the sheet and the pick roller 18 to push the sheet of media forward towards the printer, past the media separator 16. Although this torque is necessary, it can be a source of inconvenience when a user attempts to load the media tray. Consider, for example, particularly flimsy media, such as paper with a poor weight, or very thin paper. When the user grabs a few sheets and attempts to push them into the media tray 12, rather than sliding under the pick roller 18, the paper will bow. The user must manually lift up the pick assembly to insert the paper. Furthermore, when the paper moves into a following feed roller, it will still be in contact with the pick roller, and the friction between the pick roller and the paper can cause a reduction in printing quality.
It is therefore a primary objective of this invention to provide a media feeding system that has a pick roller that automatically rotates up when not feeding media, thus making it easier for a user to load a media tray of the media feeding system.
The present invention, briefly summarized, discloses a media feeding system that comprises a pick arm, one end of the pick arm having a pick roller, a media tray, a media restrainer, a motor and a drive train. The pick arm is rotatably installed above the media tray so that it can lift the pick roller up away from stacked media in the media tray, and lower it down onto the stacked media. The media restrainer can be in an up or a down position. When in the up position, it prevents the media from moving out of the media tray. When in the down position, media can move out of the media tray past the media restrainer. The drive train delivers torque from the motor to the pick arm, the pick roller and the media restrainer. The motor can operate in two directions. When operating in the first direction, the media restrainer moves into the down position, the pick roller lowers onto the stacked media and pushes a sheet out of the media tray past the media restrainer. When the motor operates in the second direction, the media restrainer moves into the up position, and the pick arm lifts the pick roller away from the stacked media.
It is an advantage of the present invention that the pick arm pulls the pick roller away from the stacked media when the media feeding system is not feeding the media to a device. Hence, it is easier for a user to load the media into the media tray. Additionally, as the pick roller is not in contact with the media when the media moves on to a following feed roller, printing quality can be improved.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment, which is illustrated in the various figures and drawings.